Temperature indicator



Filed Oct. 28, 1929 v f ...VJWWWHNNMINWHH fr M O N lhwmmmnlmmnuwuu 1 nl 9 M d M PatentedY Oct. 21, 1930 y Y EDWARD sQHA-Lsnorf WesHINGrToN,l DISTRICT encontraran l TnMrEnATURn INDICATOR The invention concerns'temperature indicators for use 1n various situations vorto serve as signal means when a prescribed* critical temperature has been reached.

Eff-.5

ing drawings in Which Figurel 'llustrates invsectiona portion .of

`a refrigerator vvall with. my invention inV x placefthereon -V Y, 31110:.5 Fig.V 2s a'frontvievv oftheindicator. Fig: 3 is a view of adetail.

, Fig'. isa viewl partly 1n section of another v form of the invention.

FigQ isa view :partly in' section oftheap;A :H5 plication of theinvention to a hot Water heat:-y

in@ system or the like. V- ig. show's in section the application of the inventiontoanother situation:

- Referring to Figures ll andf2 Ihave indi'l "1120 cated atl tlievvall of arerigerator, to which the invention isapplied. -This consistsini, f Asi'above stated, thefloat is op'enatits this particular form of -a tube 2' projecting into the ref rgerating chamberand having a vertically extend-ing portion 3 ,f outside l the Ycasing or shieldbeing usedv as at '4,ha-ving an opening-5 through :which the" tube 3A may 4be viewed. The verticalk portion ofthe tube has 4a float f6`therein closed atlthey top and having communication at-itsfV lower end With the interior vof the tube This tube 'contains a f liquid: which fis" introducedthroughfthe vport f 7 at the vend of the portion 2', said port being controlledby ascrewplug'orvalve 8 Which'is setain closed positiony after the liquidli's introduced under the desiredppressure. This pres.

sure is optiona'hbut asA an instance, mention With'safety: and Without loss'fof gasffromjthe a vpressure `of five pounds to which the .Icontents of the tube 2,13 vmaybe subjected; 'Tliek liquid lls the outer tube 2, ,3 and extends part vWay up into the lloat,l sayas'an' example tothe ji point '9, when thefdevice'is charged at a Vcertainztemperature below that at Which it is in# tended to operate as an indicator. Y Theftube 2, 3 it will benoticed is closed to atmosphere and. the device operates: Without 1 regardy to barometric Apressures and solely by Y and iwhen thetemperatureof the chamber or Space in which the device isA locatedl rises to ya `5150prescribed. degree.V

' The float Will then'fall The invention is shown inthe accompanyf A cal temperature has been reachedlis dueto -tlie lexpansion ofthe liquid contained in the tubeV 2, 3, which results inits rise intoindicator'oat'th-rough its open lower end,the gas ,the Wayto lthebottom ofV the tube; 3 I Where it Will'be-visible through the opening 5. The float may becolored'as'may be desired,{such as ruby red, to be readilyvisible, orbe opaque into. This lower end'may bere/elyopen orga Wall of the chamber, any ksuitable protecting lary action, and Willpermitthe variationsin f tion as regards action as'regardsairoregas and hence with i rvshipment may not b'e' maintained.:V s

to its lowestposition where -it'vvill bevisible through the sight opening 5 and thus indicate Thesen ofthe indicator e when this ma- 'or air bubble atthe upperfend of the/said indi# cator 'yielding and being compressed byfthe `r t rise of the liquid thereinto. 1

This action "results ink altering Y* ancy of theindicator lioat 6 sethatatgthe f ycritical temperature. Jfor whichthedevice is 65 built and calibratedlthe float` Will descendall so as to 'screenacoloredplaque back of it.: V-

lower l end to V.the access of? the lliquid -therev plugy of porous materialsuch forinsta-nce liquid to the interior fof the.f 1oat,by.a capilthe pressure of the liquid intubet2, 3,"du'ej to the plug in plajc'e thefdevicemayvjbe shippedf float zeventhough its vertical positionduring such, -or1nstance, as tetra-chloride vof carbon A f Itvwillibe noticed thatinvention"epfl-95,7 ,iS [erat'es underaxclo'sed pressure system. 1:

- The interior of thetubeQ, '3 has no communicationwith atmosphere andtheideviceis affected Vonly by temperature changesfand notby changes in? pressure of the atmospliers.il 10i)` y Y Initially, or when the device is being com Y pleted, Vthe pressure within the tube 2, 3 and upon the. liquid is such that said liquid 'willV rise within the float, compressing the gas or air therein to obtain a prescribed buoyancy thereof and when under a rise in temperature to `a; lprescribed. criticalpoint, A the liquid rises in the Vlioat,'du`e` to expansion,"and the compression of the gas or air takes place, the: float Will thenv Sink and indicate that the] critical temperaturehas'beenireacliedl f 4' The float is preferably weighted at its lower,

\ end `to keep it Vertical and, re`duce"f`riction the tube 3.' Thesel contacts may,besmetaliic- Points 01" gl'bUlS-of mercuryias indicated at f. I Y

i fi InFig I shbw forni.offapparatiisiadaph y'ed fo'rvarious situations, suchfzas rooms of :dwellings: Theliquldeontainerftube may --befcombined witha 'sylphcnseetioull adjust "ableiby *a screw l2 :by :which the pressureY on the fluid may be altered-to 'adjustithei device `toi-operateat `various temperatures as may be Sdesired..'* Y, ,y l .l fr. lnfFigathe V'device is lshown applied vto ja 4 hot'wateror steam heatingsystem.` Here a l`stu-fling 'bozl into thepipe 14: to bey subject tothe heatoftheVfluiditherein. -v i f-l-nFgqfG I showi a iioat of a difere'nt'form from that'fjdescribed'l above, inv thatV it :con-

-sistsofaclosedlhollow body 15,the sides of whicharefflexiblm suoli as thin nietal walls,

\wliich,under; expansion ofthe liquid within th-e-tubeff", willflexinwardly and compress the ga'sor airwithin-the hollow Vbodytranid fthus; change'fits buoyancy `with 'an effectlilre 4 and will rise under aafallof temperatureareshownat Vll'ainda weiglfit lat 15b.'

the/'present instance the member 1,6 Yiis a fparti of j a. transfornfier or other apparatus Eto be" safeg ardedagainst a 4rise f'of tenirferat-ure'gaboveA a1 critical point. Y

3dV of metal 4They Sarei-threaded togetherat '-whichjfserves also las' ar- `partofa stuffing-:box

*where the if tuber passes throughfthe ,cover Y or` There is alsoipaclring at 18n 'between :the llower end offtubeiclandl an internal` shoulder on as shown ,byxFig v4,01' Aas shown by Figi, 'a small ductf;7 witheazsealing valireS; may tlrefioat cubica'lglhaving .six iieiiibllefsides;- 'For certa-in purpesesfsueh .as

the safeguarding of transformers, it may beVV means for variably applying Vweight to the float.

This f may consist of, a chain 19 of metal attached. at itsupper `end at 2O to the tubeV and .withlitslower end resting-upon the Vfloat. flhen the iioat is up, several iin-ks of the chain willrest thereony andinipose their weight .upon the'leatf- Astheffioat goes down, it williberelievedof the weight of one link after the` "other, whichone by one become consecutively supported bythe chain which is suspended Vfromv above. Themovement of Vthe `iioat'feither up lor down z willptherefore progress 'inhesitatingsteps as .its burden of weight isaltered Upozia fallof temperature, the float willrise, owingto `contraction ofthe liquid within the tube, 3.0, andatheicon-yA i `sequent release of pressurefromvtheicompressiblefloat, so i thatA the float VVswill fe-Xpand 'and increase `,in buoyancy." u As. it rises itlp'icksup one vchainlinkl after the other,1.so that its-upwardfmovement is progressively retarded at 190 definite intervals, lindicative: of `'the V;pr ofg,gfres ifsive variation of temperature;,thatf-isltaling ,place inthe liquid.l i u "3 Y .Y s The pressureruponlthe'chargeof liquid in all'. forms may be .aboveffatmosphere yorlbelow,

butin charging the device fitwill be more' lclon- =ven1ent'to, jdo Vso ataapressure. above that of the atmosphere-p.zV i

,In allithe forms describelchthe float starts to zfall ata critical itemperature' and then, with: :the-ence'ptionlof :the 1modification shownpby yFig 6, .performsjitfs complete -v downward stroke.' The float is :always completely i submergedf-l v[tgwill be understood that; while 'i I. have shown` `certain* y features in only'. ,one fqgure .ofthe drawing; they are to be regarded vas associated with''inthe-:forms.shown init-he #other figures; whensnsceptible kof use there- Y Y Thus l, describe', the ltube :in Fig. f6!V as y y composedofglassfandfmetat This feature` vThis devieernaybe applied to transformerirt "unitsfor'in other combinations. Guiding pins may -bevused in theothery lforms :if desired. i l urtherithezsylphon with lits' adjustment tion of the rcontainer` wall by serewfprefssure,

bearranged-to` conveniently,connect'twitha v suitable external source v'tof ,variable :liquidif Y variations in Vpressure of sired operating temperature and pressureis reached, said valve is permanently sealed` by tightly closing it.

Reverting to Fig. 1, the section 270i the tube is 'of'metah While the section 3 is of glassvsuitably. cemented Within the metal v tube.

changes in temperature, the: vvall of said enclosing casing being non-yielding to in-y ternal and external pressures, said float, sinking When a prescribedl temperature 1s reached subject tocompression and expansion respectively by expansion and contraction of the 'l i liquid underra rise or :tall of temperature,

the Wall ofsaid tube being rigid throughoutY substantially as described.

.'8. A temperature indicator comprisinga tube containing va liquid and closed to atmosphere and a. hollow Vfloat in thefliquid tion and 'expansion of the liquid, vdue to the existence' of prescribed temperatures.

9. :Apparatus acccording toclaim 1 in Which adjusting. means` .are provided for 'varying the'capacity of kthe container, sub'- stantiallygas described.-l i y V lO. Apparatus according to claim l inV Vwhich thefloat is closed yand hasV ak flexible Wall or Walls yof non-porousmaterial.

In testimony Whereofl aiix my signature. n n

. nnvvniu)l sgHALsEY.

due to the expansion of said liquid, and the n non-yielding character of the Wall ofthe Y casing. y `2. An indicator according to claim 1 in which the interior of the float is in com munication with the tube'for the accession of the liquid,` thev said communication being by Way of a body having capacity for capillary action in connection With the liquid but substantially air vor gasy tight, substantially as described.

3. An indicator according to claim 1in i Whichv the tube containing the liquid is provided with means for varying the pressure Y on said liquid, said means consisting of an adjustingmember capable ofV remaining set, When once adjusted, for the automaticl operation of the vdevice when, a prescribed` temperature is reached. v

4. 'An indicator according to claim 1 1n Which the liquid containing tube has a sylphon extension WithV meansvfor adjusting the same.

5. Anindicator according to claim 1 in,

Which there is assooiatedv with the 'loat means for progressively removing Weight therefrom as it sinksandprogressively imposes Weight thereon as it rises, substantiallyv asrdescribed'. c Y Y v j A 6. Anindicator according lto claim 1 in which a iexible Weight lmember Vis suspended abovethe loat, progressively more and more of'said Weight, beingv re1noved`.-fron 1 the liioat v as it sinks and progressively more and more' vof said VWeight, being'imposedon said float as it rises, substantially as described.

7 A temperature indicator comprising a tube composed of a metallic temperature conducting section to, extend Within.y the space,

the temperature of which is Vto be indicated, a glass section attached tothe metallic section and in position to be visible, said tube containing liquid and closed to atmosphere,

, and a hollow oat Withinlthe glass section vvhose buoyancy changes under lthe contrac-v j ueor los 

